Water quality and contaminants in stream and surface waters collected in the Delmarva Peninsula, 2022.

This data release contains the concentration and quality assurance results for for 29 streams, sampled twice, and 1 stream sampled once at stream sites in the Chesapeake Bay Delmarva row crop region (Maryland and Delaware, USA) for the following constituent classes (count of constituents); field and water-quality parameters (9), nutrients/anions (13), dissolved organic carbon (1), per- and ployfluoroalkyl substances (PFAS) (34), assorted aqueous hazards (52), net estrogenicity (1), and major cations and trace elements (55). Samples were collected between May and July 2022. PFAS, nutrient, and water-quality constituents were analyzed at the U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL) Denver, Colorado. Anions, dissolved organic carbon, major cations, and trace elements were analyzed at the USGS Analytical Trace Element Chemistry - Common Services Laboratory (ATEC-CLS) in Boulder, Colorado. Aqueous hazards were analyzed at the USGS Integrated Water Chemistry Laboratory (IWCL) in Boulder, Colorado. Estrogenicity was analyzed at the USGS Eastern Ecological Science Center (EESC, previously Leetown Science Center) in Kearneysville, West Virgina. The respective methods associated with the analyses for constitents is listed in Table_2_Methods.